#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[])
{
	char* filename;
	if(argc !=2){
		fprintf(stderr,"usage:useupper file\n");
		exit(1);
	}
	
	filename = argv[1];
	
	if(!freopen(filename,"r", stdin))
	{
		fprintf(stderr, "could not redirect stdin from file %s\n", filename);
		exit(2);
	}
	
	execl("./upper","upper",0);
	
	perror("could not exec ./upper");
	exit(3);
	

}
